- 5.1–6.7 in
- 7.5–9.4 in
- 0.4–0.6 oz
- Moucherolle des saules (French)
- Mosquero saucero (Spanish)
- Flycatcher songs are innate, not learned like those of most songbirds. Young Willow Flycatchers reared in captivity with Alder Flycatcher tutors sang typical Willow Flycatcher songs.
- When the two species are found together, the Willow Flycatcher will keep Alder Flycatchers out of its territory. But it expends more effort to keep out other Willow Flycatchers.
- If a Brown-headed Cowbird lays its eggs in the nest of a Willow Flycatcher, the flycatcher may bury the cowbird eggs in the nest lining, or even build a completely new nest over the top of the first one.
- Breeds in moist, shrubby areas, often with standing or running water.
- Winters in shrubby clearings and early successional growth.
Mostly insects, some berries in fall.
- Clutch Size
- 3–5 eggs
- Egg Description
- Creamy white or buff dotted with dark irregular markings around large end.
- Condition at Hatching
- Helpless and with only small patches of down.
Nest built low in crotch of bush or small tree near water, on outer edge of shrub. Nest an open cup woven of weed stems, plant fibers, pine needles, shredded bark, and grass; lined with feathers, hair, rootlets, and fine materials.
Captures insects by hawking and hover-gleaning.
Overall populations appear to be declining. Southwestern subspecies is listed as Endangered, extirpated from much of its original range. Listed on the Audubon Watchlist
- Sedgwick, J. A. 2000. Willow Flycatcher (Empidonax traillii). In The Birds of North America, No. 533 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.